The present invention relates to technique for estimating an oil-diluting fuel quantity of an internal combustion engine and/or technique for controlling an internal combustion engine with an estimated oil-diluting fuel quantity.
In an internal combustion engine, fuel may leak out through the clearance between a piston and a cylinder, and dilutes oil.
U.S. Patent Application Publication US2002/0007817A1 (corresponding to Published Japanese Patent Application Kokai Publication No. 2002-13428) shows an incylinder direct fuel injection type internal combustion engine arranged to adjust a fuel injection start timing in accordance with a parameter representing adhesiveness of fuel in fuel injection on intake stroke.